Income Taxes - Differences Between Income Tax Expense at Federal Income Tax Rate and Effective Income Tax Rate (Detail)	3 Months Ended
	Jul. 31, 2016	Aug. 02, 2015
Income Tax Disclosure [Abstract]
federal income tax rate	34.00%	34.00%
U.S state income tax expense	1.40%	0.80%
tax effects of Chinese foreign exchange gains	1.10%	0.40%
increase in liability for uncertain tax positions	0.50%	0.30%
other	0.80%	1.00%
Effective income tax rate	37.80%	36.50%